Can. 931 The celebration and distribution of the
Eucharist can be done at any day and hour except those which the liturgical
norms exclude.

Can. 932 §1. The eucharistic celebration is to be
carried out in a sacred place unless in a particular case necessity requires
otherwise; in such a case the celebration must be done in a decent place.

§2. The eucharistic sacrifice must be carried out on
a dedicated or blessed altar; outside a sacred place a suitable table can be
used, always with a cloth and a corporal.

Can. 933 For a just cause and with the express
permission of the local ordinary, a priest is permitted to celebrate the
Eucharist in the place of worship of some Church or ecclesial community which
does not have full communion with the Catholic Church so long as there is no
scandal.